Quantitative assessment of changes in anterior segment morphology after argon laser peripheral iridoplasty: findings from the EARL study group.

IMPORTANCE: Argon laser peripheral iridoplasty (ALPI) could be effective in widening residual angle closure following laser peripheral iridotomy (LPI). BACKGROUND: We investigated changes in angle parameters following ALPI and its safety profile in this study. DESIGN: Retrospective, observational case series. PARTICIPANTS: The records from a single centre, of 36 patients (60 eyes) who underwent ALPI, for residual angle closure following LPI, were reviewed. METHODS: We analysed anterior chamber parameters in anterior segment optical coherence tomography (ASOCT) images using customized software pre- and post-ALPI. Paired t-test was used to compare changes. MAIN OUTCOME MEASURES: ASOCT parameters analysed included angle opening distance (AOD 500 and 750), trabecular iris surface area (TISA 500 and 750), anterior chamber width (ACW), anterior chamber volume (ACV), angle recess area (ARA), anterior chamber area (ACA), anterior chamber depth (ACD) and lens vault (LV). RESULTS: There was a mean increase in AOD 500 (0.05 vs. 0.16 mm, P < 0.001), AOD 750 (0.15 vs. 0.27 mm, P < 0.001), TISA 500 (0.010 vs. 0.038 mm2 , P < 0.001), TISA 750 (0.039 vs. 0.102 mm2 , P < 0.001), ACV (89.76 vs. 102.25 mm3 , P = 0.01), ARA 500 (0.015 vs. 0.033 mm2 , P < 0.001) and ARA 750 (0.044 vs. 0.088 mm2 , P < 0.001). There was no significant change in ACW, ACD, ACA and LV. Mean intraocular pressure (IOP) decreased post-ALPI (17.2 vs. 15.7 mmHg, P = 0.002). The mean follow-up duration was 2.1 years (range 0.5-5 years). CONCLUSIONS AND RELEVANCE: ALPI results in changes to the angle morphology and lowered IOP in eyes with residual angle closure. Our findings suggest a possible role for ALPI in eyes with residual angle closure following peripheral iridotomy.

Can an inexperienced observer accurately plot disc contours using Heidelberg retinal Tomograph?

OBJECTIVE: To examine the reliability of inexperienced observers in plotting optic disc contours on Heidelberg retinal tomography images before and after training. DESIGN: Observational study. PARTICIPANTS: One hundred eyes that were randomly selected from the Singapore Indian Eye Study. METHODS: Both eyes of subjects were imaged with Heidelberg Retina Tomograph 3 (HRT-3; Heidelberg Engineering, Heidelberg, Germany). Optic disc contours were plotted on the same images by 2 new observers on 2 separate occasions, before and after 2-hour standardized training on the skills and tools available to accurately identify and delineate optic disc contours. These plottings were compared with an experienced, trained glaucoma expert (gold standard). Agreement and variability were analyzed by interclass correlation tests and Bland-Altman plots. RESULTS: A total of 182 images (18 excluded because of poor quality) from 89 Indian subjects were included. The mean age was 53.27 ± 7.25 years and 54.8% were male. There was moderate-to-high agreement between pretraining (both new observers) and experienced observer's results (interclass correlation values range, 0.76-0.99). The interclass correlation improved for all the HRT-3 parameters after the 2 new observers were adequately trained. Comparing the interclass correlation values before and after training, the differences for mean retinal nerve fibre layer thickness for Observer 1 and all the HRT-3 parameters for Observer 2 were statistically significant. CONCLUSIONS: This study shows that it is easy to train a new inexperienced observer to plot optic disc contours on HRT images, which translates into improved and acceptable interobserver variability and agreement.

Randomized controlled trial of intravitreal ranibizumab versus standard grid laser for macular edema following branch retinal vein occlusion.

PURPOSE: To assess the efficacy of intravitreal 0.5 mg ranibizumab for the treatment of center-involving macular edema secondary to branch retinal vein occlusion (BRVO) over 1 year compared with standard-of-care grid laser. DESIGN: A prospective randomized controlled clinical trial. METHODS: A total of 36 patients with vision loss in 1 eye attributable to macular edema following BRVO were recruited from 5 institutions. Patients were randomized 1:1 to a treatment group that received 6 monthly injections of 0.5 mg ranibizumab and thereafter monthly as needed based on best-corrected visual acuity (BCVA) and central foveal thickness (CFT) assessments on optical coherence tomography scans, or a standard-of-care group that received monthly sham injections for the 1-year duration of the study. Grid laser was administered at 13 and 25 weeks in both groups if criteria for laser treatment were met. Main outcome measures included mean change in BCVA in Early Treatment Diabetic Retinopathy Study (ETDRS) letter scores from baseline to month 12. Secondary outcomes included anatomic outcomes and the percentage of patients requiring grid laser in both groups. RESULTS: Mean BCVA change from baseline was significantly greater in the treatment compared with the standard-of-care group at 12 months (12.5 ETDRS letters vs -1.6 ETDRS letters, P = .032). The mean CFT was significantly reduced in the treatment compared with standard-of-care group (361.7 µm vs 175.6 µm, P = .025). At 13 and 25 weeks, more patients in the standard-of-care group (68.4%, 50.0%) received grid laser than in the treatment group (6.7%, 8.3%). No new ocular or systemic adverse events were observed. CONCLUSIONS: Compared with standard grid laser, intravitreal ranibizumab provided significant and sustained benefits in visual acuity gain and anatomic improvement in eyes with macular edema secondary to BRVO.

Trends and factors related to outcomes for primary rhegmatogenous retinal detachment surgery in a large asian tertiary eye center.

PURPOSE: To describe trends and outcomes of vitreoretinal surgery for primary rhegmatogenous retinal detachment in a large Asian tertiary eye center. METHODS: Retrospective review of 1,530 eyes with primary retinal detachment between 2005 and 2011 managed at the Singapore National Eye Center by one of the following: scleral buckling (SB), pars plana vitrectomy (PPV), and combined SB and PPV (SB + PPV). Anatomical and functional outcomes were assessed. RESULTS: There was a trend toward PPV and PPV + SB as the primary reattachment procedure from 2005 to 2011. The primary anatomical success rate for PPV (78.6%) was worse than that for SB (88.8%) or SB + PPV (89.0%, P = 0.000). Final anatomical success rates were similar for all 3 procedures: SB 97.7%, PPV 95.2%, and SB + PPV 96.4%. Better functional success was achieved in the SB group (86.1%) than both the PPV (72.5%) and SB + PPV groups (77.5%, P = 0.000), partly attributable to the less complex nature of retinal detachments in the SB group. Older age and proliferative vitreoretinopathy were related to the poor functional outcomes in both phakic and pseudophakic eyes. CONCLUSION: There was an increasing trend toward PPV and PPV + SB as the primary retinal reattachment surgery from 2005 through to 2011. High rates of anatomical and functional outcomes were achieved with SB, PPV, and SB + PPV, proliferative vitreoretinopathy and older age were negatively correlated with the functional success in both phakic and pseudophakic eyes.

Prevalence and risk factors of epiretinal membrane in Asian Indians.

PURPOSE: To describe the prevalence of epiretinal membrane (ERM) and its risk factors in an Indian population and compare the findings with other populations. METHODS: The Singapore Indian Eye Study is a population-based survey of 3400 Asian Indians aged between 40 and 80 years. A comprehensive ophthalmic examination, standardized interviews, and laboratory blood tests were performed. Digital retinal fundus photographs were assessed for the presence of ERM following the definitions used in the Blue Mountains Eye Study (BMES). ERM was classified into a less severe form termed "cellophane macular reflex" (CMR) and a more severe form termed "preretinal macular fibrosis" (PMF) and also as primary and secondary (if it was associated with retinal pathology or cataract surgery). RESULTS: A total of 3328 persons (mean age 57.8 ± [SD] 10.1 years, and 50.2% male) provided data in this study. The age-standardized prevalence of ERM was 7.6% (95% confidence interval [CI], 6.8-8.6), CMR 4.1% (95% CI, 3.5-4.9), and PMF 3.5% (95% CI, 2.9-4.2). Older age (odds ratio [OR], 1.09; 95% CI, 1.07-1.11, per year increase), increasing myopic refraction (OR, 1.14; 95% CI, 1.07-1.22, per diopter decrease), and narrower retinal arteriolar diameter (OR, 1.02; 95% CI, 1.00-1.03, per µm decrease) were significantly associated with primary ERM. CONCLUSIONS: The age-standardized prevalence of ERM in the Indian population in Singapore was 7.6%. This is similar to Malays in Singapore (8.0%) and higher than the prevalence in whites in Australia (4.7%). Significant factors associated with primary ERM were older age, myopia, and narrower retinal arteriolar diameter.

Blowout fractures: surgical outcome in relation to age, time of intervention, and other preoperative risk factors.

We sought to describe outcome of surgical repair in patients presenting with orbital blowout fractures. This noncomparative, retrospective, consecutive case series reviewed the case notes of 63 consecutive patients who underwent surgery for a blowout fracture between November 1992 and March 2005. Risk factors for motility outcome as well as presence of enophthalmos after surgery were analyzed. Children had earlier surgery than adults (p < 001) and tended to have better motility outcome than adults. Surgery performed within the first week showed a trend for better outcome, but this was not statistically significant (p = 0.231). Assault had the best motility outcome, compared with other modes of trauma. Patients with worse preoperative motility had better outcome (p < 0.001). Enophthalmos improved significantly after surgery (p < 001). Children as compared with adults and surgery performed within the first week tended to have better motility outcome, but this was not statistically significant.

Determinants of the optic cup to disc ratio in an Asian population: the Singapore Malay Eye Study (SiMES).

OBJECTIVE: To describe the distribution and determinants of the optic cup to disc ratio (CDR) in Malay adults in Singapore. METHODS: This population-based, age-stratified study examined 3280 Malay people aged 40 to 80 years in Singapore. Participants underwent a standardized interview and an ocular examination. A slitlamp examination measured the vertical dimensions of the disc and cup, excluding areas of peripapillary atrophy and the Elschnig scleral ring. RESULTS: Vertical CDR was recorded for 3228 right eyes and 3237 left eyes. The mean (SD) CDR was 0.40 (0.15) in both eyes. The CDR in the right eye increased with age (P < .001) and was greater in men vs women (age-adjusted CDR, 0.42 vs 0.39; P < .001). In multiple linear regression, significant determinants of greater CDR were increasing age, male sex, higher intraocular pressure (IOP), lower diastolic blood pressure, lower body mass index, and previous cataract surgery. Of these, higher IOP was the most important determinant of the CDR. After excluding 149 persons with glaucoma, male sex, higher IOP, lower diastolic blood pressure, lower body mass index, and diabetes mellitus were significant predictors of greater CDR. CONCLUSION: Greater vertical CDR was related to male sex, higher IOP, lower diastolic blood pressure, and lower body mass index.

Prevalence and risk factors for refractive errors in the Singapore Malay Eye Survey.

PURPOSE: To describe the prevalence and risk factors for myopia and other refractive errors in an urban Malay population in Singapore. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: Persons of Malay ethnicity, between 40 and 80 years of age, living in Singapore. METHODS: Refractive error was determined by subjective refraction and if unavailable by autorefraction. Data were analyzed for 2974 adults without previous cataract surgery and who had right eye refraction data. Risk factor data, such as education levels and near work activity, were obtained from a face-to-face interview. MAIN OUTCOME MEASURES: Myopia, defined as spherical equivalent (SE) refraction less than -0.5 diopters (D), astigmatism as cylinder less than -0.5 D, hyperopia as SE greater than 0.5 D, and anisometropia as the difference in SE greater than 1.0 D. RESULTS: The prevalence of myopia in the right eye was 30.7% (9.4% unilateral myopia and 21.3% bilateral myopia), the prevalence of astigmatism in the right eye was 33.3% (95% confidence interval [CI, 33.0-33.5), the prevalence of hyperopia in the right eye was 27.4% (95% CI, 24.7-27.6), and the prevalence of anisometropia was 9.9% (95% CI, 9.7-10.0). There was a U-shaped relationship between increasing age and the prevalence of myopia, which was partially explained by the age-related increase in the prevalence of cataract. In a multiple logistic regression model, female sex, age, higher educational level, and cataract were associated with myopia. Adults with myopia were more likely to have astigmatism (P<0.001) in multivariate analyses. CONCLUSIONS: A quarter of older adult Malay people in Singapore had myopia. Compared with previous reports of similarly aged Singapore Chinese adults, the prevalence of myopia, astigmatism, and anisometropia was lower, whereas the prevalence of hyperopia was similar.